Method of filling and sanding rotary cut ring porous hardwood



w. H. GARNER 2,827,389 METHOD OF FILLING AND SANDING ROTARY v March 18, 1958 CUT RING POROUS HARDWOOD Filed Sept. 7. 1954 2 Sheets-Sheet 1 mwHEDm @003 Jwmkw wzEnm Om NM INVENTOR. WILLIAM HENRY GARNER BY I g M VMJ mmhEDm ATTORNEYS March 18, 1958 Filed Sept. 7, 1954 W. H. GARNER METHOD OF FILLING AND SANDING ROTARY CUT RING POROUS HARDWOOD Fig. 5

FILLING TANK I'IIIIIIII 2 Sheets-Sheet 2 NVEYOR BELT SPREIADING BLADE Fig. 8

INVENTOR. WILLIAM HENRY GARNER ATTORNEYS United States NIETHOD OF FILLlNG AND AN JENG RS'ZARY CUT RING FORGUS HARDWQGIJ William Henry Garner, Memphis, Tenn, assignor to 2; Bruce Company, Memphis, Tenn, a corporation or Delaware Application September 7, 1954, Serial No. 454,533

4 Claims. (Cl. 117-S) This invention relates to method and apparatus for forming filled and sanded flooring.

As is well known, ring porous hardwoods have open grain areas which are the spring wood and close grain areas which are the summer wood. The spring Wood and summer wood are added each year in generally concentric rings known as annular rings. These rings are not true circles and the spring wood and summer wood will vary somewhat in thickness.

From the above, it will be apparent that in cutting rotary cut veneer the knife will follow an irregular pattern through and across the annular rings or" the log. This irregularity is further modified due to the fact that the log is not a'true cylinder but is larger at one end than at the other end. The result is that relatively larger areas of both open grain spring wood and close grained summer wood appear upon the surface of the same wood section of the rotary cut veneer.

conventionally, in preparing factory finished plywood flooring having a rotary cut veneer face, the flooring blank is machined to: size and, if desired, machined to provide tongues and grooves. Then the veneer face is first sanded and subsequently filled. During the sanding process the spring wood is abraded faster than the close grained summer wood, thus leaving an uneven surface. Further, sanding across the open pores of the spring wood fails to produce a sufiiciently smooth and uniform base for the finishing as, for example, by the process of iatent No. 2,576,797 or Patent No. 2,341,161. These problems are particularly acute either where low grade or quick dried veneer is used; j

' Further, in the conventional process where the rotary cut veneer faceis sanded and conventionally filled, the process leaves the rotary cut veneer face with a painted rather than a natural look. By natural is meant the appearance of the finished surface of solid wood, to which the public is accustomed. Here, again, the lower the grade of the logs and the shorter the drying time, the less satisfactory is the result.

In accordance with the method of this invention, the veneer face does not receive an initial sanding, but is first filled, dried and then sanded. The dried filler prevents spring wood areas from being abraded by sanding faster than summer wood areas. This process results in a smooth and uniform base for the finish operation after the sanding operation.

More specifically, the filler is applied to the face surface of rotary cut veneer and is rubbed into the veneer. The excess filler is removed from the surface of the veneer and the filler is dried. After the drying operation the filled surface of the veneer is sanded.

The filler in accordance with this invention is any conventionally used wood pore filler. Thus, the filler may contain an inert non-hiding pigment, a binder and a solvent. The following are exemplary of inert nonhiding pigments: silica, gypsum, asbestine, raw sienna, burnt sienna, burnt umber, precipitated chalk, dry lakes,

2,827,389 Patented Mar. 18, 1958 ice diatomaceous earth, infusorial earth, zinc stearate, aluminum stearate and magnesium carbonate.

By way of example, satisfactory binders are raw or boiled drying oils, such as linseed oil, soybean oil, perilla oil, oiticica Oil or China-wood oil; varnishes composed of drying oils and natural resins, such as rosin and copal, or composed of drying oils and synthetic resins, such as a phenol-formaldehyde resin or an allyl starch resin; alkyd resins, such as glycerolphthalate resin; styrenated alkyd resins, such as styrene-modified phthalic alkyd resin or a styrene-modified maleic alkyd resin; polymerizable resins, such as phenol-formaldehyde, urea-formaldehyde, melamine-formaldehyde or a polyester resin; resins insoluble petroleum solvents, such as shellac, vinsol, Manila, pontianac or ethyl cellulose.

Exemplary of solvents are petroleum solvents having a kauri butanol number of from 25 to 100; coal tar solvents, such as benzol, toluol and Xylol; and a wide variety of other organic solvents, such as methyl alcohol, ethyl alcohol, isopropyl alcohol, butyl alcohol, amyl acetate, ethyl acetate, butyl lactate, acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl amyl ketone, diacetone, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether and diethylene glycol monoethyl ether.

Conventionally the inert non-hiding pigment is present in the range of about 40% to about 88% by Weight, the binder in the range of about 2% to about 20% by weight and the solvent in the range or" about 10% to about 55% by weight.

Wood pore fillers are so well known to the art that further exemplification appears to be unnecessary.

The method and apparatus in accordance with this invention will be clarified by the following description read in conjunction with the drawings, in which:

Figure 1 is a schematic plan view, partially broken away, showing the initial portion of a finishing line used in carrying out the method of this invention.

Figure 2 is a schematic plan view, partially broken away, showing the middle portion of a finishing line used in carrying out the method of this invention.

Figure 3 is a schematic plan view, partially broken away, showing the end portion of a finishing line used in carrying out the method of this invention.

Figure 4 is a side elevation of the magazine of Figure 1.

Figure 5 is a vertical section taken on the line indicated by the numbers 55 in Figure 1.

Figure 6 is a vertical section taken on the line indicated by the numbers 66 in Figure 1. I

Figure 7 is a vertical section taken on the line indicated by the numbers 77 in Figure 2.

Figure 8 is a top perspective view of a typical laminated block which can be processed by the method of this invention.

A processing line 2, adapted to carry out the process in accordance with this invention, is shown in Figures 1, 2 and 3, Figure 1 showing the beginning portion, Figure 2 the middle portion and Figure 3 the end portion of the line.

Referring to Figures 1 and 4, a rubber conveyor belt 4 travels on sheet metal plate 5 and is carried by rollers 6 and 8, which are mounted in a supporting framework ill. Roller 8 is driven by a chain 12, which is connected to a drive motor, not shown. A magazine 14, mounted above belt 4, is adapted to contain plywood flooring blocks having rotary cut veneer faces and feed them to belt 4 through opening 16.

After the Wood flooring block is placed on belt 4, it is advanced under steel pressure roller 18, which is connected to roller 8 through chain 20.

After leaving pressure roller 18, the flooring block is advanced by belt 4 to a rubber conveyor belt 22 which travels on sheet metal plate 5 and is carried by roller 24, which in turn is driven by chain 25 connected to roller 8.

Referring to Figures l and 5, belt 22 advances the flooring block under tank '26, which contains liquid filler material. Tank 26 is mounted on framework and supplies four spaced spigots '28, through which the filler material is delivered :in regulated amounts to the rotary cut veneer face of the flooring block. 7

7 Referring now to Figures 1 and *6, the flooring block is carried under blade3ll, which is bolted to support 32 secured to framework 10. Blade is formed of rubber and spreads the filler material on the veneer face of the flooring block, which is then advanced under motor driven brushes 34, 3'6 and 38, which thoroughly spread the filler material-on the veneer face of the flooring block and rub it thoroughly into the veneer. A rubber blade 35, carried bysupport 37, lies between brush 34 and brush 36 and assists in spreading the filler material.

As shown in Figure 2, the flooring block is advanced into infrared lamp tunnel 40 containing a plurality of infrared lamps 42 of, for example, about 250 watts. The

infrared tunnel insures thorough penetration of the filler into the Neneer and dries it. After passing from the in frared tunnel the sides of the flooring block are buffed by lbuifers 44 and 45 and then the top surface is buffed by motor driven bufier A8. The bufling helps to remove excess filler.

, Referring ;to Figure '3, conveyor belt 22 next passes V the flooring ,bloclcunder a reciprocating steel wood buffer 50, which further removes excess filler from the veneer face of :the flooring block. Conveyor belt 22 then ad- 111665 the flooring lblock into automatic sander 52 where the 'yeneer face .of the flooring blockis sanded so as to provide :a smooth surface and remove all excess surface filler. At its terminal end conveyor 22 is carried by :roller After the above described operations .the flooring block will be machined to size and provided with tongues and grooves as desired. The thus formed flooring block is ready for. factory or field finishing ast desired.

A block 56 shown in Figure 8 is typical of the type which can ,be'processed by this method. As shown, block a 56 has a plurality of wood .plies 58, 60 and 62, ply 58 the said areas by applyinglafillerio all of said surface,

said filler containing from about 4.0% to about 88%, by weight, of an inert pigment selected from the group consisting of silica, gypsum, asbestine, raw sienna, burnt sienna, burnt umber, precipitated chalk, dry lakes, diatomaceous earth, infusorial earth, zinc stearate, aluminum stearate and magnesium carbonate, drying the filler and then mechanically sanding to a substantially uniform level surface.

2. A process for preparing for subsequent finishing rotary cut ring porous hardwood veneer having a surface in a rough state with large adjacent areas of difiere'nt hardnesses which comprises equalizing the hardnesses of the said areas by applying a filler to all of said surface, said filler containing from about 40% to about 88%, by weight, of an inert pigment selected from the group consisting of silica, gypsum, asbestine, ,rawqsienna, burnt sienna, burnt umber, precipitated chalk, dry lakes, diatomaceous earth infusoria-l earthyzine stearate, aluminum stearate and magnesium carbonate, heating the filler until it is substantially dry and then mechanically sanding to a substantially uniform level surface. a a

3. A process for preparing for subsequent finishing rotary cut ring porous hardwood 'veneer having a surface in a rough state with large adjacent areas of different hardnesses which comprises equalizing the 'liardnesses of the said areas by applying a filler to'all of said surfaces, said filler containing from about 40% to about 88 by weight, of an inert pigment selected from the group consisting of silica, gypsum, asbestine, raw sienna, 'burnt sienna, burnt umber, precipitated chalk, dry lakes, diatomaceous earth, infusorial earth, zinc stearate, aluminum stearate and magnesium carbonate, rubbing the filler into the veneer, drying the filler and then mechanically sanding to .a substantially uniform level surface.

4. A process for preparing for subsequent finishing rotary .cut ring porous hardwood veneer having a=surface in a rough state with large adjacent areas of different hardnesses which comprises equalizing the hardnesses of the said areas by applying a filler to .all ofsa'id surface, said filler containing from about 40% to about 88%, by weight, of :an inert pigment selected from the group consisting :ofsi-lica, gypsum, asbestine, raw sienna, burnt sienna, burnt vumber, precipitated chalk, dry lakes, diatomaceous earth, infusorial .earth, zinc stearate, aluminum :stearate and magnesium carbonate, rubbing the filler into the veneer, drying the filler, boiling the filled surface and then mechanically sanding to a substantially uniform level surface. 7

References lited in the file 9f patent Newell: Coloring, Finishing and Painting Wood? 1940. j

Kinney: Furniture Repair and Refinishing, 1950. 

1. A PROCESS FOR PREPARING FOR SUBSEQUENT FINISHING ROTARY CUT RING POROUS HARDWOOD VENEER HAVING A SURFACE IN A ROUGH STATE WITH LARGE ADJACENT AREAS OF DIFFERENT HARDNESSES WHICH COMPRISES EQUALIZING THE HARDNESSES OF THE SAID AREAS BY APPLYING A FILLER TO SAID OF SAID SURFACE, SAID FILLER CONTAINING FROM ABOUT 40% TO ABOUT 88%, BY WEIGHT, OF AN INERT PIGMENT SELECTED FROM THE GROUP CONSISTING OF SILICA, GYPSUM, ASBESTINE, RAW SIENNA, BURNT SIENNA, BURNT UMBER, PRECIPITATED CHALK, DRY LAKES, DIATOMACEOUS EARTH, INFUSORIAL EARTH, ZINC STEARATE, ALUMINUM STEARATE AND MAGNESIUM CARBONATE, DRYING THE FILLER AND THEN MECHANICALLY SANDING TO A SUBSTANTIALLY UNIFORM LEVEL SURFACE. 